libqgis-dev 2.18.17+dfsg-1 / usr / include / qgis / qgsactionmanager.h

/***************************************************************************
                          qgsactionmanager.h

 These classes store and control the managment and execution of actions
 associated with a particular Qgis layer. Actions are defined to be
 external programs that are run with user-specified inputs that can
 depend on the contents of layer attributes.

                             -------------------
    begin                : Oct 24 2004
    copyright            : (C) 2004 by Gavin Macaulay
    email                : gavin at macaulay dot co dot nz
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSACTIONMANAGER_H
#define QGSACTIONMANAGER_H

#include <QString>
#include <QIcon>

#include "qgsaction.h"
#include "qgsfeature.h"
#include "qgsexpressioncontext.h"

class QDomNode;
class QDomDocument;
class QgsPythonUtils;
class QgsVectorLayer;


/** \ingroup core
 * \class QgsActionManager
 * Storage and management of actions associated with a layer.
 *
 * Actions can trigger custom code or applications to be executed
 * based on attributes of a given feature.
 */

class CORE_EXPORT QgsActionManager
{
  public:
    //! Constructor
    QgsActionManager( QgsVectorLayer *layer )
        : mLayer( layer )
        , mDefaultAction( -1 )
    {}

    /** Add an action with the given name and action details.
     * Will happily have duplicate names and actions. If
     * capture is true, when running the action using doAction(),
     * any stdout from the process will be captured and displayed in a
     * dialog box.
     */
    void addAction( QgsAction::ActionType type, const QString& name, const QString& action, bool capture = false );

    /** Add an action with the given name and action details.
     * Will happily have duplicate names and actions. If
     * capture is true, when running the action using doAction(),
     * any stdout from the process will be captured and displayed in a
     * dialog box.
     */
    void addAction( QgsAction::ActionType type, const QString& name, const QString& action, const QString& icon, bool capture = false );

    /**
     * Add a new action to this list.
     */
    void addAction( const QgsAction& action );

    //! Remove an action at given index
    void removeAction( int index );

    /**
     * Does the given action.
     *
     * @param index Index of the action
     * @param feat Feature to run action for
     * @param defaultValueIndex Index of the field to be used if the action has a $currfield placeholder.
     * @param scope Expression context scope to add during expression evaluation
     *
     * @note available in python bindings as doActionFeature
     */
    void doAction( int index,
                   const QgsFeature &feat,
                   int defaultValueIndex = 0,
                   const QgsExpressionContextScope &scope = QgsExpressionContextScope() );

    /** Does the action using the expression engine to replace any embedded expressions
     * in the action definition.
     * @param index action index
     * @param feature feature to run action for
     * @param context expression context to evalute expressions under
     * @param substitutionMap deprecated - kept for compatibility with projects, will be removed for 3.0
     */
    // TODO QGIS 3.0 remove substition map - force use of expression variables
    void doAction( int index,
                   const QgsFeature& feature,
                   const QgsExpressionContext& context,
                   const QMap<QString, QVariant> *substitutionMap = nullptr );

    /** Does the action using the expression builder to expand it
     *  and getting values from the passed feature attribute map.
     *  substitutionMap is used to pass custom substitutions, to replace
     *  each key in the map with the associated value
     *  @note available in python bindings as doActionFeatureWithSubstitution
     *  @deprecated use QgsExpressionContext variant instead
     */
    Q_DECL_DEPRECATED void doAction( int index,
                                     const QgsFeature &feat,
                                     const QMap<QString, QVariant> *substitutionMap );

    //! Removes all actions
    void clearActions();

    /**
     * Return a list of all actions
     */
    QList<QgsAction> listActions() const;

    //! Return the layer
    QgsVectorLayer* layer() const { return mLayer; }

    /** Expands the given action, replacing all %'s with the value as
     *  given.
     * @deprecated use QgsExpression::replaceExpressionText() instead
     */
    Q_DECL_DEPRECATED QString expandAction( QString action, const QgsAttributeMap &attributes, uint defaultValueIndex );

    /** Expands the given action using the expression builder
     *  This function currently replaces each expression between [% and %]
     *  placeholders in the action with the result of its evaluation on
     *  the feature passed as argument.
     *
     *  Additional substitutions can be passed through the substitutionMap
     *  parameter
     *  @deprecated use QgsExpression::replaceExpressionText() instead
     */
    Q_DECL_DEPRECATED QString expandAction( const QString& action,
                                            QgsFeature &feat,
                                            const QMap<QString, QVariant> *substitutionMap = nullptr );


    //! Writes the actions out in XML format
    bool writeXML( QDomNode& layer_node, QDomDocument& doc ) const;

    //! Reads the actions in in XML format
    bool readXML( const QDomNode& layer_node );

    /**
     * Get the number of actions managed by this.
     */
    int size() const { return mActions.size(); }

    /**
     * Get the action at the specified index.
     */
    const QgsAction& at( int idx ) const { return mActions.at( idx ); }

    /**
     * Get the action at the specified index.
     */
    QgsAction operator[]( int idx ) const { return mActions[idx]; }

    /** @deprecated Initialize QgsPythonRunner instead
     * @note not available in Python bindings
     */
    Q_DECL_DEPRECATED static void setPythonExecute( void ( * )( const QString & ) );

    /**
     * Returns the index of the default action, or -1 if no default action is available.
     * @see setDefaultAction()
     */
    int defaultAction() const { return mDefaultAction < 0 || mDefaultAction >= size() ? -1 : mDefaultAction; }

    /**
     * Set the index of the default action.
     * @param actionNumber index of action which should be made the default for the layer
     * @see defaultAction()
     */
    void setDefaultAction( int actionNumber ) { mDefaultAction = actionNumber ; }

  private:
    QList<QgsAction> mActions;
    QgsVectorLayer *mLayer;
    static void ( *smPythonExecute )( const QString & );

    void runAction( const QgsAction &action,
                    void ( *executePython )( const QString & ) = nullptr );

    int mDefaultAction;

    QgsExpressionContext createExpressionContext() const;
};

#endif